Category: Python Answers

Sometimes, we want to catch multiple exceptions in one line with Python.

In this article, we’ll look at how to catch multiple exceptions in one line with Python.

How to catch multiple exceptions in one line with Python?

To catch multiple exceptions in one line with Python, we can catch multiple exceptions in 1 line.

For instance, we write

try:
    #...
except (IDontLikeYouException, YouAreBeingMeanException) as e:
    pass

to add an except block that catches the IDontLikeYouException and YouAreBeingMeanException in 1 line.

Conclusion

To catch multiple exceptions in one line with Python, we can catch multiple exceptions in 1 line.

Sometimes, we want to verify host key with Python pysftp.

In this article, we’ll look at how to verify host key with Python pysftp.

How to verify host key with Python pysftp?

To verify host key with Python pysftp, we create a pysftp.Connection object.

For instance, we write

try:
    ftp = pysftp.Connection(host, username=user, password=password)
except:
    print("Couldn't connect to ftp")
    return False

to create a pysftp.Connection in a function to try to connect to the host with the given user and password.

If it fails, then an exception will be raised and we know the host key isn’t valid.

Conclusion

To verify host key with Python pysftp, we create a pysftp.Connection object.

Sometimes, we want to process escape sequences in a string in Python.

In this article, we’ll look at how to process escape sequences in a string in Python.

How to process escape sequences in a string in Python?

To process escape sequences in a string in Python, we call decode to decode the string.

For instance, we write

my_string = "spam\\neggs"
decoded_string = bytes(my_string, "utf-8").decode("unicode_escape")
print(decoded_string)

to call bytes with my_string and the 'utf-8' encoding to convert the string to bytes.

And then we call decode with 'unicode_escape' to return the decoded string without the escape characters.

Conclusion

To process escape sequences in a string in Python, we call decode to decode the string.

Sometimes, we want to log in to a website using Python’s Requests module.

In this article, we’ll look at how to log in to a website using Python’s Requests module.

How to log in to a website using Python’s Requests module?

to log in to a website using Python’s Requests module, we can make a POST request with request.post with the credentials.

For instance, we write

import requests

url = "http://example.com/userinfo.php"
values = {"username": "user", "password": "pass"}

r = requests.post(url, data=values)
print(r.content)

to call requests.post with the request url and the request data.

And then we get the response body from r.content.

Conclusion

to log in to a website using Python’s Requests module, we can make a POST request with request.post with the credentials.

Sometimes, we want to concatenate text files in Python.

In this article, we’ll look at how to concatenate text files in Python.

How to concatenate text files in Python?

To concatenate text files in Python, we can open each file and call write to write the contents of each file to a file.

For instance, we write

filenames = [
    "file1.txt",
    "file2.txt",
    # ...
]
with open("path/to/output/file", "w") as outfile:
    for fname in filenames:
        with open(fname) as infile:
            for line in infile:
                outfile.write(line)

to call open to open the output file with write permission

Then we loop through the file names strings in filenames with a for loop.

In the loop, we call open to open the input file.

And then we loop through each line with another for loop.

In it, we call outfile.write to write the line into the output file.

Conclusion

To concatenate text files in Python, we can open each file and call write to write the contents of each file to a file.